JP3128464B2 - Facsimile communication method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to ITU-T Recommendation T30.
The present invention relates to a facsimile communication method that can be used for a facsimile apparatus conforming to the G3 standard, which has been standardized by G3, and particularly to a facsimile communication method in which the communication protocol is speeded up.

[0002]

2. Description of the Related Art A communication protocol in a G3 facsimile apparatus according to ITU-T recommendation T30 is performed according to a signal sequence shown in FIG.

In FIG. 14, each signal indicated by a thin solid line indicates a low-speed signal. This low-speed signal includes TSI and NS as signals from the transmitter side.
There are S, EOP, and DCN, and signals from the receiver side include NSF, CSI, DIS, CFR, and MCF.
TCF and PIX from transmitter side indicated by thick solid line
Is a high-speed signal. CNG from the transmitter side and CED from the receiver side, which are indicated by thin dotted lines, are tone signals.
The dial on the transmitter side is a signal for the line network.

[0004] The transmitter dials the other party in response to a transmission request from the operator. Thereafter, when the line is connected, the tone signal CNG is transmitted.

When the receiver detects an incoming call and connects to the line,
The tone signal CNG from the transmitter is detected. When this is detected, the tone signal CED, the low-speed signals NSF, CS
I, DIS are sent to the transmitter.

The transmitter transmits a tone signal CE from the receiving side.
D, receiving the low-speed signals NSF, CSI, and DIS;
If the SF maker code matches your transmitter, T
Transmits SI and NSS at low speed. Further, a training check signal TCF is transmitted at a high signal speed specified by NSS.

[0007] The receiver checks the TCF, and if there is no error, sends out a reception preparation confirmation signal CFR.

[0008] The transmitter transmits the reception preparation confirmation signal CFR.
Is received, the image data PIX is transferred at the high signal speed specified by the NSS.

[0009]

However, in the above-described communication protocol in the facsimile apparatus of the G3 standard, it takes about 13 seconds until image data is actually transmitted. This time is more than twice as long as, for example, the transmission time of one A4 size document is about 6 seconds at a communication speed of 14.4 KBPS.

Therefore, it is desired to reduce the control procedure time until image data transmission, and the following method has been considered as a method of reducing the control procedure time.

That is, a control procedure for communicating a communication procedure signal by a low-speed modem and a control procedure for communicating a communication procedure signal by a high-speed modem are provided. As shown in the signal sequence diagram of FIG. After that, the transmitting side transmits a high-speed procedure request signal (corresponding to NSS, hereinafter referred to as SNSS
), And the high-speed procedure request signal SNSS
Is called by the called party in response to the high-speed procedure request signal (corresponding to the NSF;
F) is transmitted by the low-speed modem, and after transmitting the high-speed procedure acknowledgment SNSF, the control procedure is performed by the high-speed modem.

More specifically, as shown in the flowcharts of FIGS. 10 and 11, on the transmitting side, when the transmission key is pressed by the operator, dialing of the destination telephone number is performed (step 11). After completion of the dialing, an interval of several seconds is taken (step 12).
This interval is taken because the line is not connected immediately after dialing. Next, a timer T (other party response waiting period) is started (step 13), and then CNG of 1100 Hz is transmitted for 0.5 seconds (step 14). Then, after an interval of 75 ms (step 15), The procedure request signal SNSS is transmitted at a low speed (step 16).

Next, the reception of the low-speed signal and the CED is prepared, and the timer T1 is started (step 17).
When the high-speed procedure request signal SNSS is transmitted at a rate of two per CNG signal, the value of the timer T1 is appropriately about 0.8 seconds. Until the above-mentioned timer T1 times out, a process of detecting whether or not the high-speed procedure acknowledgment SNSF has been transmitted from the receiver (step 18), and CED, NSF, CS
A process for detecting whether or not I and DIS have been transmitted (step 19) is performed.

In step 18, the high-speed procedure acknowledgment SN
If SF is detected, the procedure proceeds to the high-speed procedure (Step 29). If not detected, the procedure proceeds to Step 19. If the CED or the like is detected, the procedure proceeds to the standard procedure (Step 28). If a timeout has occurred without any detection (YES in step 20), the second high-speed procedure request signal SNSS for one CNG signal is transmitted (step 21), and the timer T2 is started (step 22). . After that, the same processing as the above-mentioned steps 18 to 20 is repeated (steps 23 to 25).
To determine whether the timeout has occurred (step 2
6). If the timer T has not timed out, the process proceeds to step 14, while if the timer T has timed out, it is determined that the other party has not responded and the line is disconnected (step 2).
7).

The receiving side detects whether there is an incoming call as shown in the flowchart of FIG. 12 (step 3).
1) If there is an incoming call, the line is connected (step 32), and the timer is started (step 33). And CN
G and SNSS are not detected (step 34
When the timeout occurs (YES in step 36), it is determined that the partner device is a device that does not have the high-speed procedure, and CE is performed according to the procedure of the G3 device.
D and the like are transmitted (step 37), and the procedure proceeds to the standard procedure (step 38).

If CNG is detected in step 34 (YES in step 34), another timer is started (step 41). Next, if the other device is a device having a high-speed procedure, an SNSS
Is transmitted, it is detected whether SNSS is transmitted (step 42).

If the SNSS is not detected (NO in step 42) and a timeout occurs (Y in step 43)
ES), the process proceeds to step 37, where CED or the like is transmitted (step 37), and the process proceeds to the standard procedure (step 38).

On the other hand, when the SNSS is detected in step 35 and when the SNSS is detected in step 42, it is determined that the partner device is a device having a high-speed procedure, and a high-speed procedure acknowledgment SNSF is transmitted. (Step 39), proceed to the high-speed procedure (Step 40).

By employing such a communication method, a control procedure after transmitting the SNSF can be performed at a high speed.

On the other hand, the calling side determines a tone signal (for example, a dial tone, a ringback tone, or a busy tone) from the station by the modem, and sets a redial condition in accordance with the determined tone signal. It is carried out.

However, in the above communication method, the calling side must repeatedly send a high-speed procedure request signal after dialing. Normally, the tone signal is determined by checking the tone frequency and the ON / OFF pattern by the modem. However, when the modem is transmitting a signal, the modem cannot generally detect the tone. Therefore, as described above, the high-speed procedure request signal SNSS
Is repeatedly transmitted, it is difficult to recognize the tone signal from the station.

The present invention has been made in view of the above circumstances, and has as its object to provide a facsimile communication method capable of determining a tone signal from a station while realizing a high-speed procedure in the communication method.

[0023]

In order to solve the above-mentioned problems, a facsimile communication method according to the present invention has a control procedure for transmitting and receiving a communication procedure signal by a low-speed modem and a control procedure for transmitting and receiving a communication procedure signal by a high-speed modem. After the calling-side dialing, the calling side repeatedly sends CNG and the high-speed procedure request signal by the low-speed modem without detecting the line connection, and the called side receiving the high-speed procedure request signal transmits the high-speed procedure request signal. A facsimile communication method for communicating a subsequent control procedure by a high-speed modem when a high-speed procedure confirmation response, which is a response to a request signal, is transmitted by a low-speed modem, wherein the CNG and the high-speed procedure request signal are repeatedly transmitted for a predetermined period. Later, CN
It is characterized in that only G is repeatedly transmitted.

[0024]

According to the above arrangement, even if the tone signal transmitted from the station cannot be determined during the period in which the CNG and the high-speed procedure request signal are repeatedly transmitted, only the CNG is transmitted after the lapse of the period. Is transmitted repeatedly, and the high-speed procedure request signal is not transmitted.
By checking the N / OFF pattern, the tone signal can be reliably determined.

[0025]

【Example】

(Embodiment 1) Hereinafter, the present invention will be described with reference to the drawings showing the embodiment.

FIG. 1 is a block diagram showing the configuration of a facsimile apparatus according to the present invention.

The operation unit 1 includes various keys such as one-touch dial keys and numeric keys, a liquid crystal display, and the like. By the user operating the above keys,
The operation signal is provided to the main control unit 3.

The reading section 2 is composed of an image sensor such as a CCD, reads a document placed on a document table (not shown), and outputs the image data to the main control section 3.

The main control unit 3 controls the entire apparatus, and is a microcomputer peripheral device such as a ROM (not shown) storing a microcomputer and a control program, and a RAM temporarily storing various data. And controls the encoding and decoding of the image signal and the execution of the communication procedure.

The recording section 4 is constituted by a thermal printer or a laser printer or the like, and drives a head based on image data supplied from the main control section 3 to perform printing on recording paper.

The low-speed modem 5 is a low-speed modem defined by ITU-T Recommendation V21, and is used for communication in a normal control procedure. On the other hand, the high-speed modem 6 is a high-speed modem defined by ITU-T recommendations V27ter, V29, V33, and V17. The tone signal from the station is determined by monitoring the tone frequency and the ON / OFF pattern by the modem. The modem continuously monitors the tone signal during communication, but generally cannot detect the tone when transmitting the signal.

The network control unit (NCU) 7 is connected to the line 8 and detects a call signal from the line 8 to determine an incoming call as a process at the time of receiving a call, and performs a main control as a process at the time of calling. For example, dialing of the telephone number of the other party is performed.

Next, the procedure before the high-speed procedure in the facsimile apparatus of the present invention will be described with reference to the flowcharts of FIGS.

[Procedure on Transmitter Side] FIG. 2 is a flowchart showing a part of the control procedure before the high-speed procedure on the transmitter side, and FIGS. 3 and 4 show the control procedure of the remaining part. It is a flowchart.

On the transmitting side, first, when the transmission key is pressed by the operator, dialing of the other party's telephone number is performed (step 51), and an interval of several seconds is taken after completion of the dialing (step 52). Next, the timer T0 (first partner response waiting time) is started (step 53), and the CNG at 1100 Hz is set to 0.5.
The high-speed procedure request signal SNSS is transmitted (step 56) after an interval of 75 ms (step 55).

Next, the timer T2 is started (step 57). Until the timer T2 times out, the high-speed procedure acknowledgment SNSF is received from the receiver side.
For detecting whether or not has been transmitted (step 58)
And a process of detecting whether CED, NSF, CSI, and DIS have been transmitted (step 59).

At step 58, the high-speed procedure acknowledgment SN
If SF is detected, the process proceeds to the high-speed procedure (step 75).
If D or the like is detected, proceed to the standard procedure (step 7).
4). If no time is detected and a timeout occurs (YES in step 60), the high-speed procedure request signal SNSS
Is transmitted (step 61).

Then, the timer T3 is started (step 62). Thereafter, the above steps 58 to 60 are performed.
The same processing as described above is repeated (steps 63 to 65). When the timer T3 times out, it is determined whether or not the timer T0 times out (step 66). If the timer T0 has not timed out, the process proceeds to step S54, and the process of repeatedly transmitting CNG and the high-speed procedure request signal SNSS is continued.

On the other hand, if the timer T0 times out, the timer T1 (second party response waiting period) is started (step 67), and only CNG is repeatedly transmitted.
To ensure that the tone signal sent from the station can be recognized. That is, CNG is transmitted (step 68), the timer T4 is started immediately (step 69), and CE is
A process (step 70) for detecting whether D, NSF, CSI, and DIS have been transmitted is performed.

If a CED or the like is detected, the procedure proceeds to the standard procedure (step 74). When the timer T4 times out without detecting the CED or the like (YES in step 71).
Then, it is determined whether or not the timer T1 has timed out (step 72). If the timer T1 has not timed out, the process proceeds to step 68 to continue the process of repeatedly transmitting only CNG. On the other hand, if the timer T1 has timed out, it is determined that the other party has not responded and the line is disconnected (step 73). When a busy tone is recognized, a line disconnection process is performed.

[Receiver side procedure] On the receiver side, a reception control procedure is executed according to the flowchart of FIG. 12 shown in the conventional example.

FIG. 5A shows that the transmission procedure of the flowcharts shown in FIGS. 2 to 4 repeatedly transmits CNG and the high-speed procedure request signal SNSS until the time T0 elapses, and the time T0 elapses. In a later period T1,
FIG. 9 is a diagram illustrating a state in which only CNG is transmitted. (B) of FIG. 11 is a diagram showing a state in which CNG and the high-speed procedure request signal SNSS are repeatedly transmitted in the entire partner response waiting period T for comparison.

As is apparent from FIG. 5A, C
Even if the tone signal transmitted from the station cannot be determined during the period T0 (first partner response waiting period) during which the NG and the high-speed procedure request signal SNSS are repeatedly transmitted, after the period T0 elapses, Since only CNG is repeatedly transmitted and the high-speed procedure request signal SNSS is not transmitted, the modem can reliably determine the tone signal by checking the tone frequency and the ON / OFF pattern.

Embodiment 2 Hereinafter, another embodiment of the present invention will be described.

FIG. 6 is a flowchart showing a part of the control procedure before the high-speed procedure on the transmitter side according to the present embodiment, and FIGS. 7 and 8 are flowcharts showing the control procedure of the remaining part. is there. In these flowcharts, common steps to the first embodiment are denoted by common step numbers.

The difference between the facsimile communication method according to the first embodiment and the facsimile communication method according to the present embodiment is that the transmission of the high-speed procedure request signal SNSS performed during the period T0 is devised. That is, before transmitting each high-speed procedure request signal SNSS, the presence or absence of a tone from the station is detected, and when a tone is detected, transmission of the high-speed procedure request signal SNSS is mainly performed.

Accordingly, as is clear from the flowcharts of FIGS. 6 to 8, during the period T0, CNG is transmitted (step 54), and after an interval (step 55), the presence or absence of a tone from the station is detected. (Step 80). The tone signal recognition processing (tone frequency and ON / OFF pattern detection) is always performed except at the time of signal transmission.

In step 80, if no tone from the station is detected, the high-speed procedure request signal S
Send NSS at low speed (step 56), step 5
Go to 7. On the other hand, if a tone from the station is detected, the process proceeds to step 57 without transmitting the high-speed procedure request signal SNSS.

Before the transmission of the second high-speed procedure request signal SNSS for one CNG, the presence or absence of a tone from the station is detected (step 81). The procedure request signal SNSS is transmitted at a low speed (step 61), and the process proceeds to step 62. On the other hand, if a tone from the station is detected, the high-speed procedure request signal SN
The process proceeds to step 62 without transmitting the SS. It should be noted that the timer values in step 57 and step 62 are different depending on whether the processing has passed step 56 or step 61 or not.

FIG. 9A shows a state in which the transmission of the high-speed procedure request signal SNSS is stopped in relation to the tone signal received from the station by the transmission procedure of the flowcharts shown in FIGS. FIG. (B) of FIG.
Are, for comparison, all CNs during the partner response waiting period T.
FIG. 7 is a diagram showing a state in which G and a high-speed procedure request signal SNSS are repeatedly transmitted.

As shown in FIG. 9A, if a tone is detected before the transmission of the high-speed procedure request signal SNSS, the modem does not transmit the high-speed procedure request signal SNSS. Subsequently, the tone frequency and the ON / OFF pattern can be checked.
Therefore, the tone signal can be recognized more reliably than in the case of the first embodiment.

When a busy tone is recognized, a line disconnection process is performed. Recognition of the tone signal can be performed during the period from the transmission of CNG to the transmission of the next CNG if the tone detection state is ensured. However, in FIG. 9A, the busy tone is recognized. The line disconnection process at the time is not shown, and SNS caused by tone detection or non-detection
This indicates non-transmission or only transmission of S.

On the other hand, when the ringback tone is recognized, the high-speed procedure request signal SNSS is repeatedly transmitted without disconnecting the line even after the recognition. Since it is not particularly necessary to stop the transmission of the high-speed procedure request signal SNSS for tone signal recognition after the ringback tone has been recognized, the high-speed procedure request signal SNSS is output regardless of tone detection after tone recognition. The signal may be transmitted, or after the tone recognition, in the period T1, not only the CNG but also the high-speed procedure request signal SNSS may be repeatedly transmitted.

The first and / or second partner response waiting period may be made adjustable by the user, and the first partner response waiting period T0 is set to be equal to the partner response waiting period T shown in the conventional example. It is also possible to adopt a mode in which the second party response waiting period is additionally provided.

[0055]

As described above, according to the present invention, CNG
Even if it is not possible to determine the tone signal transmitted from the station during the period in which the high-speed procedure request signal and the high-speed procedure request signal are repeatedly transmitted, only the CNG is repeatedly transmitted after the lapse of the period, and the high-speed procedure request signal is Since transmission is not performed, the modem can check the frequency of the tone and the ON / OFF pattern to reliably determine the tone signal.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a facsimile apparatus of the present invention.

FIG. 2 is a flowchart showing a part of a transmission side process in the facsimile communication method of the present invention.

FIG. 3 is a flowchart showing the remaining part of the transmission-side processing in the facsimile communication method of the present invention.

FIG. 4 is a flowchart showing the remaining part of the transmission-side processing in the facsimile communication method of the present invention.

FIG. 5 is a diagram showing a state in which transmission of a high-speed procedure request signal is stopped during a period T1 according to the present invention;

FIG. 6 is a flowchart illustrating a part of a transmission-side process in a facsimile communication method according to a second embodiment of the present invention.

FIG. 7 is a flowchart showing the remaining part of the transmission-side processing in the facsimile communication method according to the second embodiment of the present invention.

FIG. 8 is a flowchart showing the remaining part of the transmission-side processing in the facsimile communication method according to the second embodiment of the present invention.

FIG. 9 is a diagram showing a state in which transmission of a high-speed procedure request signal is stopped in relation to a tone signal received from a station during a period T0 of the present invention.

FIG. 10 is a flowchart showing a part of a process in which a calling side repeatedly sends a high-speed procedure request signal by a low-speed modem without detecting a line connection.

FIG. 11 is a flowchart showing the remaining processing of the flowchart of FIG. 6;

FIG. 12 is a flowchart showing processing considered to be performed on the receiving side corresponding to the processing on the transmitting side shown in FIGS. 10 and 11;

FIG. 13 is a signal sequence diagram showing a communication procedure according to FIGS. 10 to 12;

FIG. 14 is a signal sequence diagram illustrating a communication procedure in a G3 standard facsimile machine.

[Explanation of symbols]

 Reference Signs List 1 operation unit 2 reading unit 3 main control unit 4 recording unit 5 low speed modem 6 high speed modem 7 NCU

Claims (1)

(57) [Claims] 1. A control procedure for transmitting and receiving a communication procedure signal by a low-speed modem and a control procedure for transmitting and receiving a communication procedure signal by a high-speed modem. After dialing on the calling side, the calling side detects a line connection. CNG with low speed modem without doing
When the called party receiving the high-speed procedure request signal sends a high-speed procedure confirmation response, which is a response to the high-speed procedure request signal, with the low-speed modem, the subsequent control procedure is communicated with the high-speed modem. A facsimile communication method for transmitting a CNG and a high-speed procedure request signal repeatedly for a predetermined period, and then repeatedly transmitting only the CNG.